Replying to Options for Insane amounts of external hard drive space

So I am not filming with a Canon Xh-A1 while the picture is amazing one of the issues i face now is storage space for the footage. Each tape takes up 30 GB of storage space. I am editing on a MAC book with a 200 GB 5400 HD, 2.3 GHZ Processor, and 2gb or RAM. I am going to upgrade the Ram to 4 and the hard drive to 360 7200. But my main issue is i need around 4 TB of external storage that i can access fast. So my main two options are buying 4, 1TB Hard drives and conecting firewire. Now my question is i have been reading about Hard Drive towers could i buy one of these for its aorund 100 bux and then just fill it with 1tb internal drives then connect it to firewire to my mac book?